Dunham Rd would be my choice, as shown on the BCMT map. SCRD Park. The mill site appears to behind a security gate. Maybe there is a ramp there: possibly it is for those who have legal access or maybe day use, but I doubt you could leave a car there.
From Dunham Rd/ McNair Ck it is easy paddling to Bain Ck or N’wards. You lucky folk get to avoid crossing Montague Channel, too.
There is also another beach at the creek mouth 400 m S of Dunham Rd we call Dakota Ck but we don’t show it (yet) on the BCMT map. It is mostly used by locals (dog walkers by day and revellers by night?) but also part of the same Park, I believe.
Pl let us know your experience using this launch. It looks good from both land and sea. Here’s hoping the local residents are friendly, unlike those at Tuwanek!